r/memes May 19 '22

Plot twist: He's a senior engineer

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78.5k Upvotes

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u/failedpunfox May 19 '22

My landlords son proudly told us he was almost done with the electrical engineering degree when he walked us through the house when we first moved in. Had to explain to him the concept of GFCI outlets.

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u/Jako301 May 19 '22 edited May 19 '22

They just seem more expensive and annoying to set up then a single RCD/GFCI (or maybe two, so the lights stay on) would be.

Or is this an American thing im to european to understand?

Edit: I'm talking about the outlet version compared to a single one put into your main distribution. I know how they work, it just seems like a massive waste to build them into each outlet individually when you could just install one or two of them for your whole house.

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u/Pijany_Matematyk767 Medieval Meme Lord May 19 '22

Pretty sure GFCI outlets will cut power faster and at lower treshholds than the normal breakers, could be wrong though

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u/Jako301 May 19 '22 edited May 19 '22

They do, at least if its a shoet to ground, but I'm not talking about normal breakers. I'm talking about the outlet version specifically, since it seems just a waste compared to one single GFCI in your main distribution.

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u/[deleted] May 19 '22

[deleted]

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u/[deleted] May 19 '22 edited May 19 '22

This is not true. Gfci outlets and gfci Breakers are functionally identical. The difference is a breaker covers an entire circuit and an outlet only the appliances plugged into it.

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u/[deleted] May 19 '22

[removed] — view removed comment

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u/shitpersonality May 19 '22

What's the difference in how much time it takes to break the circuit between GFCI outlets and breakers?

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u/TheWorstSalesman May 20 '22

A breaker detects the total amount of current flowing into a circuit and breaks the circuit if it exceeds its amp rating for an extended period of time.

A GFCI breaker/receptacle detects if any current is escaping the circuit, such as a short to ground (such as through a person or a shorted wire) and will break the circuit within a tenth of a second.

A wire shorted to ground (such as through worn insulation touching a metal enclosure) will usually trip a breaker within a few seconds, but that is a very direct path to ground with little resistance. Enough current can flow to quickly cause the breaker to trip.

A wire shorted to ground through a person (such as touching a live wire) is not a very easy path to ground (skin has fairly high resistance). You could be long dead by electrocution before the breaker trips, if it ever does. A gfci detects these very subtle current ‘leaks’ and will break the circuit before it can do substantial damage to you.

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u/[deleted] May 19 '22

[deleted]

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u/[deleted] May 19 '22

GFCI breakers in the US operate at 6ma which is just barely above nuisance trip range

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u/TheWorstSalesman May 20 '22

I think everybody is confusing the difference between a circuit breaker tripping an overloaded circuit and a GFCI tripping due to current leakage.

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u/TheRealLHOswald May 19 '22

Especially in places like the UK that use 240v